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Frankw
06-07-2006, 10:07 PM
Having problems with overhead stick 7018, icicles droops etc. (standard CWB coupon) when I cap it looks like our curtains.:o

Anyone have any tips?

koreanbeefcake
06-07-2006, 10:09 PM
what size rod?

i usually use 3/32 and run about 130 amps. make your to keep good close arc lenght.

enlpck
06-08-2006, 07:35 AM
Think of overhead as being just like flat, upside-down. Really. Shove the rod in, almost, and move at a moderate speed. Too slow will give you grapes all over, just like too fast will give you poor fusion and voids. When running flat, you can run slower than ideal, because the metal will just build up a bit an won't run anywhere. Overhead, you CAN'T shovel the metal in as easily as flat.

Frankw
06-08-2006, 05:11 PM
It's 1/8" 7018 at approx 115 A, standard drag at 15, Miller Dialarc 250 or Lincoln Idealarc 250. My technique is obviously the problem, have no consistency. Have no problem with flat, horizontal or vertical up.

Enlpck...how much push on the rod do you use?

Regards Frank.

BillC
06-08-2006, 07:32 PM
Frank,

You've got to watch the puddle; it is the key to any welding in any position. Watch the puddle fill in behind you as you move. If you watch it overfill you will get grapes. Overhead is just as easy as flat.

Have Fun!

jamesdart
06-08-2006, 08:59 PM
keep a very tight arc length. i also prefer to keep no angle at all when doing overhead. stick the rod strait into the puddle. wont hurt to turn your heat up 5 or so amps.

Engloid
06-09-2006, 10:58 AM
As mentioned above, just imagine its flat....just don't think you can really dump the metal to it in one pass like you can flat.

enlpck
06-09-2006, 12:44 PM
It's 1/8" 7018 at approx 115 A, standard drag at 15, Miller Dialarc 250 or Lincoln Idealarc 250. My technique is obviously the problem, have no consistency. Have no problem with flat, horizontal or vertical up.

Enlpck...how much push on the rod do you use?

Regards Frank.
The rod angle does want to be a little drag. When I say push the rod in I mean keep the rod pushed into the groove. About to where the flux drags. When I was learning, the guy teaching me said, basicly, "shove it till the rod is ready to bend, then MOVE". Try a few beads on flat plate to get the speed. You really don't want a lower current. On plate, run faster and faster until you start to see lack-of fusion and skipping, then slow down a little. If you try to put in too much metal, you get grapes.

Another thing on overhead is that your grinder is your friend. You don't have the luxury of burning in as much as in other positions, so wire brush the weld dead clean between passes, and give a touch with a hard wheel where needed to get the surface ready for the next pass. I figure I'll use 20% more rod on overhead than vertical or flat, because I like to U-out where the next bead will go a little bit. Not a lot, just until it is smooth. In the long run, this is a lot faster and easier than cutting a weld out to do it over.

Frankw
06-09-2006, 04:06 PM
Thank you gentlemen for the replies.

Enlpck...I cannot use a grinder on the CWB test (would be nice).

The CWB plate is a 90 edge and a 30 beveled edge.

I have passed the 1g, 2g, 3g positions big difficulty with 4g.

Info can be found here...http://www.grbwelding.com/images/CWBTest.pdf

enlpck
06-10-2006, 09:21 PM
Thank you gentlemen for the replies.

Enlpck...I cannot use a grinder on the CWB test (would be nice).

The CWB plate is a 90 edge and a 30 beveled edge.

I have passed the 1g, 2g, 3g positions big difficulty with 4g.

Info can be found here...http://www.grbwelding.com/images/CWBTest.pdf
Ok.. I have been blessed with being able to use a grinder on most of my tests. Then best adice I can give is try running a bunch of beads on the face of a plate at different speeds. You wil be able to see what the result is fairly easily and get a good idea of where you want to run.

Do they at least allow you files? (common arc does. or at least did) If so, dress the end of a medium-sized rat tail to about a 60 or 70 degree angle, and put a good handle on it. Use it like a U-gouge chisel on an air hammer. Same thing with a square file... dress it like a diamond-point chisel. If you keep the edge sharp, you don;t need impact. You can push it in enough to get the crud out and dress the surface by hand and dig a little, kind of like carving wood. And, you still have the file for smoothing.

If no files, you can do the same thing to the pointy end of a chipping hammer, but you need to sharpen it fairly often, as it isn;t as hard as the file. The cleaned, U-ed out groove helps a lot.

BillC
06-10-2006, 10:13 PM
Frank,

Where do you have your problems? Is it every pass, just the root passes, or ??? You are running stringers, correct?

How long have you been practicing 4G? To be honest, I was really dissapointed after my first overhead welds... I had always imagined it to be mystically challenging; separating the men from the boys. Turned out to be really easy; much easier than vertical. The only challenge was staying steady with my arms overhead at an awkward extension...

Everybody's given you great advice. You should be able to tell by looking at the puddle what is going on... If it starts to turn to crap then pull out and change your settings. It won't get any better as the part gets hotter...

Regards,

enlpck
06-11-2006, 08:29 PM
Another thing (that actually applies to all welding) is get relaxed. In the real world. you don't usually have control over the conditions when you weld, but in the shop, you do. I get laughed at for running overhead coupons with the arm on the mount pointing down and lowaered all the way, nd sitting on the floor braced against a bench leg. Real stable, good visibility for the weld, I can relax and not have to work to brace myself, and get into the zone. I may get laughed at, but my coupons bend clean. Much better welders than me can;t get a clean bend to save their lives, mostly because the have trouble staying within the parameters and because they stress about the test.

TEK
06-11-2006, 09:03 PM
It's 1/8" 7018 at approx 115 A, standard drag at 15, Miller Dialarc 250 or Lincoln Idealarc 250. My technique is obviously the problem, have no consistency. Have no problem with flat, horizontal or vertical up.

Enlpck...how much push on the rod do you use?

Regards Frank.

Good advice so far. Only thing I can add is about the angle of the rod. You will probably get your best results by keeping an open mind and not getting fixated on any one angle. Many times,in many situations, I have had to push,not drag, to get a good pass. As others before me have said---Watch the puddle--If it starts to get too long then use less angle.Your arc and puddle combination,in overhead, should look much the same as flats.

rattle
06-14-2006, 02:16 AM
Another thing (that actually applies to all welding) is get relaxed.

That is excatly what took me the longest to figure out with overhead. To start with I have to hold on to something (wall or whatever) otherwise I would be all over the place.

Are CWB coupons not fillet welds? 4F instead of 4G? 3/8" plate with 1/4" backing strip.

In BC we were alowed grinders. A wire wheel makes it nicer.

jokers81
06-14-2006, 09:40 AM
The FIRST RULE of Welding, GET COMFORTABLE!

Frankw
06-16-2006, 09:13 PM
Thanks again for the tips.

Turned up the heat a little.

After some more practice plates, there is a definite improvement. Can now get in the first two passes (both have stop/starts) cleanly. My filling is also much better. Now just need to work on getting the capping stringers to look neater.

Good to get expert advice from the experts.:)

MuddMachine
06-18-2006, 09:57 AM
Glad it's working out for you finally. Problem I see so often is people running too cold. As others have said, turn up the machine a bit and pick up the speed. Some people like to look at the overhead plate and weld left to right, some like to pull it towards them instead. The most important thing is to be comfortable.

Here in Ontario you are NOT allowed to use a grinder at all. Wire wheel, or saw blade, sure. As long as no stone hits the weld. Besides, grinder on a test plate? Anyone can make a mess and grind it out until you do your cap.

rattle
06-18-2006, 09:01 PM
We were had a grinder with a wire wheel.

I think Ontario is a bit different though. There was a guy that had completed his first level in Ontario and moved to BC and had to redo his first year. I guess it is different once you have a red seal but before they don't recognize it intra-provincial.

MuddMachine
06-19-2006, 09:00 AM
The testing 'should' be the same across Canada. There is different practices tho. While I was in BC doing some shut downs I noticed ALOT of 6011 being run downhand, this is totally frowned upon in Ontario. I have the paperwork to go intertprovincial (red seal), just have to fill it out and do the exam. Apparantly Ontario is changing over to red seal over the next few years.

Sberry
06-19-2006, 03:04 PM
ALOT of 6011 being run downhand, this is totally frowned upon in Ontario What was it being ran on? We do it all the time on poor fitup and light materials for general field fab, it has its place.

Bluzzin
06-19-2006, 06:15 PM
ALOT of 6011 being run downhand, this is totally frowned upon in Ontario

I was taught in school this year that its okay to do root weld v down with 6011 as long as full penetration was achieved. Then cover with 7018 v up. I did this as instructed and when destruction tested in press the metal failed, weld was fine.

Bluzzin

rattle
06-19-2006, 07:26 PM
6011 is downhand is frowned on? 7018 downhand must be really bad then, eh? :cool:

What they teach you in school is the correct way to do things. In the field it is sometimes a little different. It took me a bit to figure things out after school. Like for instance how to weld 1/2" plate to 3/4" plate that is just all rust.

I don't think Ontario is really that different from BC or even the USA for that matter. You will always find some 'hacks' and some really good welders everywhere. IMHO anyways.

coalsmoke
06-21-2006, 02:40 PM
I don't think Ontario is really that different from BC or even the USA for that matter. You will always find some 'hacks' and some really good welders everywhere. IMHO anyways.

well put :cool:

Frankw
06-21-2006, 10:10 PM
Well guys did the test today, just awaiting the cut and bend results, managed to get the capping level.

Thank you for all your advice.;)

MuddMachine
06-23-2006, 07:14 PM
ALOT of 6011 being run downhand, this is totally frowned upon in Ontario

I was taught in school this year that its okay to do root weld v down with 6011 as long as full penetration was achieved. Then cover with 7018 v up. I did this as instructed and when destruction tested in press the metal failed, weld was fine.

Bluzzin

The metal failed but weld was fine? Ive never done a coupon with those results. If that happened then the test failed.

Downhand period, is frowned upon here. Never worked anywhere in my 22 years as a welder where they'll let you run downhand with any rod.

BC is ALOT different from Ontario, I lived in BC for a few years and worked in a few shops out there. When I was out there doing field work people were welding everything down hand, from light structures to big slide shutes.

Point taken tho, everywhere you go you'll find hacks.

coalsmoke
06-23-2006, 08:52 PM
to my knowledge and from what i have seen, nothing here in BC gets welded downhill if its by some form of code or specs, unless its a root pass or in someone's farmyard. All our structures that I have worked on when I was doing tilt-up buildings was vert uphand. At risk of misquoting, I believe some of our online pipelining members here consistently run downhand root passes with 6010 (or similar variation). Fab shops are something else and I can't comment on them for general lack of exposure (only been in a couple, which is not enough to make a sweeping statement about).

OldSparks
06-24-2006, 02:05 AM
A little rambling about downhill stick. In a shop you are working with detailed blueprints. The customer pays to have the work done as specified to guarantee a certain lifespan. Now lets say this piece of duckwork/breaching goes into service for 10 years and now a part of it needs replacing. The burnt out 3/8" plate is cut back to where it's still 1/8" thick and a new piece welded in. Not at all feasible or necesary to weld uphand as the new lifespan is only until the next shutdown and future replacement.

An example of downhill welding on pressure parts is the overlay of tubework in high erosion areas.,,you don't want to risk an uphand on tubes worn as thin as .115". Then there are the various attachments that are actually welded to the tube. Again because the tubes can be of various unknown thickness special downhill codes are approved. Many companies have their own preapproved procedures to which you test. It's also common to weld storage tanks downhand and backgouge. Often with the tee's being x-rayed.

As for schooling...A qualified welder can test at a college or vocational school for 3 prequalified welding procedures involving downhill stick (6G position)
PWP#2....6010 root and hot pass downhill on 6" pipe, 7018 uphill to finish
PWP#8....same as PWP#2 except also has to pass on 2" at the same time
PWP#11...downhill 6010 on 16" diameter pipe
"These are approved for work in a shop working on boiler and pressure parts in accordance with CSA B1 and the ASME Boiler and Pressure Vessel Code"
Don't know the actual benifit of having these tickets as the hiring company will probably want you to test to their own procedure. Might look good on your resume along side the normal uphill pipe PWP#7

Although not meant for structural and critical support areas, downhill does still serves a purpose.

Bluzzin
06-24-2006, 09:02 AM
The metal failed but weld was fine? Ive never done a coupon with those results. If that happened then the test failed.


The test piece was welded, then put in a 150 ton press, somewhere over 100 tons the piece broke, it did not break at the weld so how would that be a failed test ? Instructor seemed to think the weld was pretty good.

Bluzzin

BillC
06-24-2006, 10:08 AM
Per AWS D1.1:

a. No cracks greater than 1/8 long in any direction
b. Cumulative length of all cracks between 1/32 and 1/8 shall be less than 3/8 long
c. Corner cracks greater than 1/4 long that do not initiate from a weld defect require a new test specimen

So, per AWS criteria, cracks in the base metal are allowed as long as they are not weld-related. I would not expect a tear in the middle of the test piece in the base metal as there shouldn't be any stress risers. The edges are stress risers so corner cracks are not unexpected.

What are the accept reject criteria for the CWB tests?

Regards,

OldSparks
06-24-2006, 10:56 AM
I can remember back when I was learning to weld. We'd cut our practice coupons out of metal salvage the school had obtained and go our merry ways on different positions. Once you started putting in decent looking welds, you did bend tests. A handfull of students had a batch that broke along side weld. After initial shock of how hard passing a welding test could be, it was decided we had just welded up some AR or other alloy plate that didn't like bending. Can't recall ever seeing a proper mild steel plate break that didn't have obvious welding flaws.

MuddMachine
06-24-2006, 12:38 PM
At risk of misquoting, I believe some of our online pipelining members here consistently run downhand root passes with 6010 (or similar variation).I'll try and cover everything you guys have quoted since my last post... here goes. In regards to the quote above. Pipelining involves downhand, that much I know but this is all done to code/procedure and correct me if i'm wrong but thay test you in this procedure, correct???



The burnt out 3/8" plate is cut back to where it's still 1/8" thick and a new piece welded in. Not at all feasible or necesary to weld uphand as the new lifespan is only until the next shutdown and future replacement.Understood and I agree, If it'll last till the next, make it happen. But when the next shutdown comes and it's time to replace it, there would be no downhand involved unless you were following a procedure. This is the way it's been on all the job's ive been involved in.



"These are approved for work in a shop working on boiler and pressure parts in accordance with CSA B1 and the ASME Boiler and Pressure Vessel Code"Again, if it's to code that is a different story. I havent been involved in the pressure vessel industry at all. From what I know and from what I have done, a shop environment is a controlled environment and that means that you shouldnt have to weld anything out of position (flat and horizontal only) excluding procedures and/or codes.



What are the accept reject criteria for the CWB tests?I'll be honest here and tell you that I'm not 100% sure exactly what the criteria is. From what Ive seen over the years alot of it has to do with the inspector himself, exceptions may vary slightly. If you bend a plate and there is a 1/8" long crack in the weld itself they will let it go as long as it's not a gaping crack, more or less a hairline crack will pass. Undercut is frowned upon. If they spot 1/32" undercut in a few spots they usually let it go. If there is alot of undercut along the weld, be it 1/32 even, it'll fail. If the cover pass is 1/8" above flush they might give you some static about it. They usually tell me no more than 1/16 above flush. And NO grinding at all throuout your test. Wire wheel is acceptable but dont let them see a grinding stone anywhere near your test plate.



A handfull of students had a batch that broke along side weld. After initial shock of how hard passing a welding test could be, it was decided we had just welded up some AR or other alloy plate that didn't like bending. Can't recall ever seeing a proper mild steel plate break that didn't have obvious welding flaws.These are my thoughts exactly. Im not to clear as to what Bluzzin is saying. Like OldSparks said, if it's mild steel it shouldnt break at all. If it broke along side the weld then there is some issues with the type of steel you are using or it's a bad weld, plain and simple.

Lets not blow thios out of proportion here. I know there is code and procedures for DH welding but it's not the norm. When I was in BC I saw lots of welding being done with 6011 DH. While you may be able to get away with it on non critical stuff, we just dont do that here. Most of the stuff I saw was not critical welding, it will hold but sometimes even tho you can get away with it that doesnt make it ok. While installing a line at the sawmill in Quesnel I saw plenty of DH welding on framework and stuff like that. Is it critical? No. Will anyone die or get injured should it fail? No. Will it fail? In my opinion, probably, especially on machinery where there is vibration and such. From what I was exposed to it looked like most of the DH welding was done because it was quickerand in the not so critical areas. One thing I did NOT see was all position wire being used anywhere. Actually I saw no wire feed at all. So basically it's fast and easy and thats why it was being done. When Im in the field here we use wire feed wherever possible. It's as fast as 6011 DH and way stronger.

Dont take this the wrong way guys. Im not an inspector or a supervisor or anything special. What I am is a welder with over 20 years experience who takes a great deal of pride in his work. I know what Im doing and I know whats right or wrong (regardless of what the 'book' says). When I do something I do it right. Do I cut corners? Of course I do, but i know what I can get away with as well. Stuff that is right out in the open is done properly. Work that is hidden and out of the way is a different story. Basically if my boss can see it I wont be cheating cuz he will come to me and say "WTF is that?"

enlpck
06-25-2006, 10:54 PM
Can't recall ever seeing a proper mild steel plate break that didn't have obvious welding flaws.
I had a batch of coupons that were cut the 'wrong way' to the roll of the metal, so the weld was along the length of the the roll, and the bend across it. Every weld done on that batch fialed in the HAZ.

Frankw
07-28-2006, 08:39 PM
Well guys I just got notification that I passed my CWB overhead..Whoopeee.:D

Once again thanks for all the expert help, it did make a big difference.

Now have 4 SMAW positions.

Now to tackle the pipe stuff.:cool:

BillC
07-28-2006, 09:11 PM
Congratulations!

Finney
07-28-2006, 11:56 PM
99% of all high pressure gas (700psi average) lines are done down hill. 6010 root 7010 0r 8010 hot pass, filler and cap. These are very critical welds. You will test before you start the job and some companies will make you test again after 6 months. So you could test today because your 6 months is up and the job ends next week and you start a new job the following week and have to test again.
Some companies are using duel shield for tie in welds now. 6010 root and wire for the hot pass, filler and cap.

IndianOutlaw
07-29-2006, 04:15 AM
One little tip I did not see mentioned by anyone. When running 7018 and you are not allowed the use of a grinder, this may help: say you are getting down to the last 1 1/2 -2 inches and you are getting ready to stop & change rods, just before you break the arc, speed up for 1/4" to 3/8" keeping the arc tight before you pull off & break the arc. This will leave a narrow stop in which the slag will fall right off.